import logging; logging.basicConfig(level=logging.INFO)

import asyncio, os, json, time

from datetime import datetime

from aiohttp import web

def index(request):

    return web.Response(body=b'<h1>Awesome</h1>', content_type='text/html') # 此处content_type添加后正常访问，不添加则下载文件

async def init():

    app = web.Application() # loop=loop 会提示loop弃用，此处为空

    app.router.add_route('GET', '/', index)

    app_runner = web.AppRunner(app)

    await app_runner.setup()

    srv = web.TCPSite(app_runner, '127.0.0.1', 9000) # 原有的方法弃用，使用此方法运行成功

    await srv.start()

    logging.info('server started at http://127.0.0.1:9000...')

    return srv

loop = asyncio.get_event_loop()

loop.run_until_complete(init())

loop.run_forever()

